This invention relates to bed frames and, more particularly, to bed frames which have an adjustable width.
Bed frames for supporting a box spring and mattress above a floor typically include a pair of spaced, parallel, horizontally disposed side rails, and a pair of spaced, parallel, horizontally disposed end rails which extend substantially transversely between the side rails for holding the side rails in spaced, parallel relationship. The end rails typically comprise a pair of elements which are locked together.
A problem has long existed in the art because certain frame members of the above type have not provided positive interlocking engagement between the end rail elements and have required the use of a large number of fasteners. As a result, the assembly and disassembly of the end rail elements is time consuming and complicated and if, by chance, the width has been assembled too narrow or too wide for the particular box spring and mattress, the box spring and mattress may have to be completely removed before any readjustment of the width can be made.
Commonly assigned U.S. Pat. No. 4,078,270 to Nowell provides a solution to this problem by providing means for fastening together the elements of a transverse member of a bed frame, while still allowing for adjustments in the width of the bed frame. However, one of the disclosed embodiments requires a separate sleeve that circumscribes and protrudes outwardly from both transverse elements. In the other embodiment, the fastening means provides for adjustments in the transverse width, but does not fasten the two transverse elements together; the two elements are in the shape of C-shaped channels which are received within one another to restrain the elements in all directions except axially.
Commonly assigned U.S. Pat. No. 3,757,361 to Harris et al. discloses an adjustable transverse member that has rivets on one transverse element that are receivable in keyhole slots in the other transverse element. However, the width of the transverse member can be adjusted only to the predetermined spacing of the rivets and keyhole slots. Accordingly, variations in width can be made to accommodate queen-size or king-size bedding, but slight adjustments in width to compensate for minor variations in width of an inch or so for a particular size of bedding, such as queen-size, cannot be readily made.
Commonly assigned U.S. Pat. application Ser. No. 956,186, to Nowell filed Oct. 30, 1978, discloses another form of an adjustable bed frame. In this arrangement, keyhole slots are provided in one end rail member, protrusions are provided on the other end rail member which are receivable in the slots, and one of the slots has teeth that are engageable by a spring loaded panel. The disadvantages of this structure are the difficulties and expense in producing the end rail members with slots and protrusions, and the tab for releasing the pawl is difficult for a user to reach because the pawl and tap are positioned above the lower edge of the end rail members.
Another problem with prior art bed frames is in providing a bracket for limiting transverse movement of the bedding relative to the bed frame. Typically, this is accomplished by riveting the bracket to the side rail, and the rivet is disposed vertically with the rivet head exposed and protruding upwardly from the top surface of the side rail and bracket. As a result, the box spring does not rest upon the side rail or bracket immediately adjacent to the rivet, and this results in undesirable tension forces in the box spring and bending of the box spring.